Path: ...!eternal-september.org!feeder2.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: WM Newsgroups: sci.math Subject: Re: Incompleteness of Cantor's enumeration of the rational numbers Date: Tue, 26 Nov 2024 10:11:22 +0100 Organization: A noiseless patient Spider Lines: 42 Message-ID: References: <74bdc0f14fd0f2c6bfd9ac511a37f66b41948ac4@i2pn2.org> <0d6d06a888e15ed2042aca8ec7e6ebb93590b7bc@i2pn2.org> <8a2aedd8383a84ceef2fd985ac0bf529e2a0eccf@i2pn2.org> <3fe6ef31f562e0ddf598de46cf864986ca909687@i2pn2.org> <9cb8aec671200bb6d71582fd607b876b7ec4c83a@i2pn2.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 26 Nov 2024 10:11:23 +0100 (CET) Injection-Info: dont-email.me; posting-host="0a0757352dd822c88488d80397f1f101"; logging-data="3561144"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+FPUdFPf1TWIL76Pvp5I8Ip0U2uy7ABW4=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:y3uJ93wmCoA5VxO0peIngE9ym1M= Content-Language: en-US In-Reply-To: <9cb8aec671200bb6d71582fd607b876b7ec4c83a@i2pn2.org> Bytes: 3811 On 25.11.2024 22:05, joes wrote: > Am Mon, 25 Nov 2024 13:18:28 +0100 schrieb WM: >>> But there is no finite set with ALL natural numbers. >>> Like usual, you mess up with your qualifiers. >> ℕ is fixed, that means |ℕ| is fixed. > What does that have to do with it? It is impossible to add or to delete an element. It is impossible to change |ℕ| by 1 or more. > >>>>> Limit theory only works if the limit actually exists >>>> If limits exist at all, then the limit of the sequence 1/10, 1/10, >>>> 1/10, ... does exist. >>> But the concept of 1/10th of an infinte set does not exist.. >> It does. > It has the same cardinality. Yes, it is much. > >>>>> You can get things that APPEAR to reach a limit, but actually don't. >>>> But if infinite sets do exist, then the set ℕ does exist, and all its >>>> elements are members of finite intervals (0, n]. >>> No, any given element is a member of a finite set, but you can't then >>> say that ALL are in such a set. >> All are in the union of all finite sets. > Why not just directly take N, made up of finite numbers? Why not? Do it. Consider the black hats at every 10 n and white hats at all other numbers n. It is possible to shift the black hats such that every interval (0, n] is completely covered by black hats. There is no first n discernible that cannot be covered by black hat. But the origin of each used black hat larger than n is now covered by a white hat. Without deleting all white hats it is not possible to cover all n by black hats. But deleting white hats is prohibited by logic. Exchanging can never delete one of the exchanged elements. Therefore we have here, like in all Cantor-pairings, the same impediment and further disussion is futile: You must deny logic. I do not. Regards, WM